Automatic strand starting mechanism



Dec. 26, 1950 R. R. BASTIAN AUTOMATIC STRAND STARTING MECHANISM Filed Dec). 27, 1949 FURNACE FURNACE MOVIIVG BLADE FIXED BLADE INVENTOR. fizard E 574294;

Patented Dec. 26, 1950 UNITED STATES PATENT OFFICE AUTOMATIC STRAND STARTING MECHANISM Richard R. Bastian, Toledo, Ohio Application December 27, 1949, Serial No. 135,164

Claims. 1

This invention relates to apparatus for the manufacture of fibers of glass or the like and is particularly directed to a device to facilitate the automat c starting of the ends of broken fibers into the strand drawing device to assure continuous operation.

In the apparatus for the mechanical drawing of fibers as di c osed in my copending aopllca tion Serial No. 42.804, a plurality of glass strands issue from an orifice plate, which forms the bottom of a tank in which a molten glass batch is contained. The fibers are drawn or pulled outwardly from the tank by a perforate belt or the like disposed at an angle to the path that the fibers would follow by gravity alone. The fibers are caused to adhere lightly to the lower surface of the pulling belt by a negative fluid pressure established within the be t. Bv utilizing a direction of travel for the belt which is away from the normal vertical path of the fibers a winch-like action is obtained and the fibers can be attenuated with greater speed and greater uniformity than would be the case if the belt were vertically disposed adjacent a falling strand. The fibers thus pulled or attenuated attain the speed of the moving belt and are easily removed therefrom by air pressure, to be collected either singly or as a mat.

In the operation of a machine of this character for the manufacture of bonded mat, it is necessary to eliminate the small beads which form on the end of each strand as it moves initially away from the orifice plate. The beads form whenever a strand breaks and must be restarted and it is the practice in machines of this character to break the beads off by hand and to restart the strand by throwing it against the moving belt.

The primary object of the present invention is to provide an automatic device to restart a broken strand and to dispose of the bead that is associated herewith.

Another object of the invent on is to provide an automatic strand starting mechanism which is maintained in o eration continuously in the path of a freely falling fiber so that any fiber falling by gravity will engage a bead cutoff mechanism and be restarted.

Still another object of the invention is to provide means to establish an air current tending I to move a freely falling fiber against an attenuating belt, which current becomes effective whenever the fiber is relieved of the weight of a starting bead.

Other objects and advantages of the invention will become apparent from the following detailed description of a preferred form, reference being had to the accompanying drawings, in which:

Figure l is a diagrammatic perspective view of an automatic strand starting mechanism embodying the present invention, and Figure 2 is a cross-sectional view taken on line 2-2 of Figure 1.

Referring to the drawings, the present invention is shown in conjunction with a glass fiber drawing a paratus including a furnace Ill having an orifice plate I l in its lower wall. A single strand of glass designated S is indicated as issuing therefrom for purposes of explaining my improvement. The glass strand is attenuated by engagement with a fiber drawing belt l2 having a perforate surface so that air may be drawn through the belt. The belt is preferably an endless unit and has its point of closest approach to the fiber S laterally removed from the path that the fiber would follow if it were free to fall under the influence of gravity alone.

The interior of the belt I is, in the first stages, subject to a negative air pressure by connecting it with an exhaust fan l3, as is disclosed in my copending application Serial No. 42,804.

A baflie plate 14 tapers upwardly toward the belt and terminates closely adjacent thereto at, or approximately at, the end of suction box.

. Side walls It cooperate with the bottom baiile M to form a chamber open at its front adjacent the strand S and otherwise closed at the top by the belt. It will thus be seen that an air current passes continuously into the chamber and up through the belt.

Adjacent the bottom of the chamber formed by bottom baffle l4 and side walls It, there is disposed a stationary cutting blade l8 and a cooperating moving cutting blade 20. A motor 22 causes reciprocation of the moving cutter blade with respect to the stationary blade. The spacing of the teeth of the two blades is such that a fine glass strand entering between the stationary teeth will be severed completely by the teeth of the moving blade.

When strand S is first formed, it moves away from the orifice plate I l by gravity and is accompanied by the formation of a small solid bead of glass which must be removed from the final product. The head is quite heavy and causes the strand to move almost perpendicular with relation to the orifice plate and thus past the adjacent face of the belt l2. As the bead moves down, pulling the strand S behind it, the bead engages a deflecting plate 24 disposed at such an angle that the strand is deflected laterally as a unit. The strand above the bead is thus caused to move into the cut-off device comprising the stationary and movable blades. The severed head is directed into a hopper or other disposal unit. When the strand S is freed of the weight of the head, it no longer moves by gravity, but is influenced by the air current passing into the space between the walls It and bottom bafile I and is thus carried up against the moving belt I2. The resulting fiber is then attenuated in the normal manner and can join the rest of the fibers being drawn to form the final product, which is thus free from the beads or solid glass particles that might otherwise be found therein.

Motor 22 is operated continuously during the operation of the machine and any strand that becomes broken is promptly restarted. A broken strand may be caused by discontinuities in the glass batch, such as bubbles or the like. When a strand breaks, the orifice from which it has previously issued floods with molten glass until the glass achieves a sufficient weight to move away from the orifice by gravity. The accumulated weight is in the form of the bead previously mentioned which must be eliminated if the resulting mat is to be commercially satisfactory.

While the invention has been disclosed in connection with a particular form of attenuating mechanism, it will be appreciated that numerous modifications and changes may be made without departing from the scope of the appended claims.

What I claim is:

1. In an apparatus for manufacturing glass fibers which includes a container for molten glass, means for projecting the molten glass in separate strands, a perforate continuous strand attenuating belt, and means for creating a low pressure area within the belt to hold the glass strands onto the surface thereof, the improvement comprising severing means positioned in alignment with free-falling glob-bearing glass strands and adapted to sever the glob from the strand, means for directing the glob-bearing glass strands through the severing means, and an enclosure surrounding a portion of the perforate continuous belt, said enclosure connected at one end to the means for creating a low pressure within the belt and open at another end adjacent the path of the free-falling glob-bearing strands so that the cut strands are urged upwardly into contact with the continuous attenuating belt.

2. In an apparatus for manufacturing glass fibers which includes a container for molten glass, means for projecting the molten glass in separate strands, a perforate continuous strand attenuating belt, and means for creating a low pressure area within the belt to hold the glass strands onto the surface thereof, the improvement comprising an automatic cut-off device positioned in alignment with free-falling globbearing glass strands and adapted to sever the glob from the strand, a bafile inclined toward the automatic device for directing glob-bearing glass strands therethrough, and a fluid-tight casing surrounding a portion of the perforate continuous belt, said casing being connected at one end to said means for creating a low pressure within the continuous belt and open at an end adjacent the path of the free-falling glob-bearing strands so that the cut strands are urged upwardly into contact with the continuous belt by the means for creating the low pressure.

3. In an apparatus for manufacturing glass fibers which includes a container for molten glass, means for projecting the molten glass in separate strands, a perforate strand attenuating continuous belt, and means for creating a low pressure area within the belt to hold the glass strands onto the surface thereof, the improvement comprising an automatic cut-off device positioned in alignment with the free-falling glob-bearing strands and adapted to sever the glob from the strand, a bafiie inclined toward the automatic cut-01f device to direct glob-bearing glass strands therethrough, and a fluid-tight casing including therein the belt conveyor and connected to said means for creating a low pressure area within the conveyor, said casing having an open end ad acent the path of the free-falling glob-bearing glass strands so that the cut strands are urged upwardly into contact with the continuous belt by said means for creating a low pressure.

4. In an apparatus for manufacturing glass fibers which includes a container for molten glass, means for projecting the molten glass in separate strands, a perforate continuous strand attenuating belt, and means for creating a low pressure area within the belt to hold the glass strands onto the surface thereof, the improvement comprising an automatic cut-off device positioned in alignment with the free-falling glob-bearing strands and adapted. to sever the glob from the strand, means for directing the glob-bearing glass strands to and through the automatic cutoff device, and a fluid-tight casing comprising side walls partially surrounding the continuous belt and a'bottom wall inclined from a point not higher than the automatic cut-01f device to a point adjacent the continuous belt, said casing being connected at one end to said means for creating a low pressure area within the belt and being open at another end adjacent the path of the free-falling glob-bearing strands in order 1too urge the cut strands up onto the continuous elt.

5. In an apparatus for manufacturing glass fibers which includes a container for molten glass, means for projecting the molten glass in separate strands, a perforate continuous strand attenuating belt, and means for creating a low pressure area within the belt to hold the glass strands onto the surface thereof, the improvement comprising severing means positioned in alignment with the free-falling glob-bearing strands and adapted to sever the glob from the strand, :1 baffle inclined toward the severing means to direct the glob-bearing glass strands to and through the severing means, and a fluid-tight casing comprising side walls partially surrounding said continuous belt and a bottom wall inclined from a point not higher than the severing means to a point adjacent the continuous belt, said casing being open along the top thereof and along one side and so positioned that the open side is adjacent the path of the free-falling glob-bearing glass strands so that the suction created by said means for producing a low pressure area within the belt moves the cut strands upwardly into contact with the belt.

RICHARD R. BASTIAN.

No references cited. 

